Chain door-bolt lock.



R. T.- ATKIN.

CHAIN DOOR BOLT LOOK. APPLICATION funn nn.15.19o5.

H Il Z4' l PATENTBD AUG. 1, 1905.

Unir-an srafrns PATENT OFFICE.

RICHARD THOMAS ATKIN, OF NEW YORK, N. Y.

CHAIN DOOR-BOLT LOCK- To a/Z whom, t may concern:

Be it known that I, RICHARD THOMAS AT- KIN, a citizen of the United States, and a resident of New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Oliain Door-Bolt Looks, of which the following is a specification.

My invention relates to locks, particularly to a chain-bolt door-lock. It has for its object to provide a look into whichthe chainbolt can be inserted from the outside and only released by a key inserted from the outside or inside.

'It has for a further object to provide means for automatically releasing thev bolt from the tumblers when the key is inserted.

It has for a further object to provide a device of the character set forth embodying advantages in point of simplicity and inexpensiveness of construction and perfect operation.

In the drawings, Figure 1 designates a horizontal sectional view of a door-frame and door hung therein in partly-open position and having my device applied. Fig. 2 is a fragmentary sectional view of a door having my device applied and shown in vertical section. Fig. 3 is a fragmentary sectional view of a door having my device applied and shown in horizontal section. Fig. 4 is a detail'view, partly in section, of my chain-bolt.

In all the iiguresv of the drawings illustrating my invention like reference characters designate the same parts.

Referring to the drawings, 1 designates the door-casing, and 2 the door hung therein. The lock 3 is secured in a recess 4 in the edge of the door and comprises a casing 5, in Which are mounted transversel T-slidable tumblers 6 and 7, located in the same vertical plane and their inner edges 8 vand 9 meeting and each being provided with a forward semicircular recess, formingin conjunction a circular bolt-receiving recess 10, and rear recess, forming in conjunction an elongated recess 1 1, in which is located a cross-bar 12 for operating the tumblers in unison by means of a key-shaft 13, one end of which is attached to said cross bar and the other end projecting through a keyhole 14 in the inside of the door.

To provide for the operation of the tumblers by turning the cross-bar, one end of a plate 15 is secured to the tumbler 7 and the other end bears against the face of the tumbler 6, and one end of a plate 16 is secured to Specification of Letters Patent.

Application filed March l5, 1905. Serial No. 250,300.

Patented Aug. l, 1905.

the tumbler 6 on the opposite side of the tumblers and the other end bears against the face of the tumbler 7.

Spiral springs 17 and 18 are located at the rear of the tumblers and one end of the spring 1,7 bearing against the end of the lock-casing and the other end bearing against the plate 16, and one end of the spring 18 bears against the lock-casing and theother end against the plate 15. It will be understood from this arrangement that the tumblers are independently slidable, so that their uneven front faces may be engaged by a stepped key 20 and slid in, so as to properly register the recesses in the forward ends to form the circular recess 10, and then returned to their normal position after the key is withdrawn or be returnedto their normal position after they have been slid in in unison by the cross-bar 12, operated by the key 12/, and then released.

The bolt 21 comprises a bullet shaped body portion 22, the inner end being provided with a circular recess 23, adapted to be engaged by the edges of the tumblers bordering the recess 10 when it is inserted into the hole 24, formed in the lock-casing and door, and the outer end is provided with a hollow flange 25, in which a spring 26 seats. This spring is compressed between the face of the door and said flange when the bolt is inserted and locked by the tumblers, and when the bolt is released by the tumblers the spring automatically forces it out of the hole 24.

To limit the movement of the tumblers in either direction, screws 24 and 24Z project from the lock-casing in the line ment of said tumblers. e

One end of a chain 27 is connected to an of moveeye 28 on the outer end of the bolt and the other end to keeper 29 on the door-frame. Thus when the bolt is locked by the tumblers the door can only be opened slightly, governed by the length of the chain, and when the bolt is released by the tumblers the door can be fully opened.

From the foregoing it will be understood that to release the bolt from the outside the key 20 is inserted into engagement with the ends of the tumblers andA they are forced back in unison against the action of the springs 17 and 18, and as soon as the bordering edges of the tumblers 'forming the recess 10 clear the circular groove in the bolt said bolt is automatically thrown out by I the spring 26, and to release the bolt from the inside the key 12 is inserted into engagement with the squared end of the key-shaft 13, and it is turned by bringing one end of the crossbar 12 against the plates 15 and 16 on the tumblers, forcing said tumblers kback in unison against the action of the springs 17 and 18, and as soon as the ,bordering edges of tumblers forming the recesses 10 clear the circular groove in the bolt said bolt is automatically thrown out by the spring 26.

l do not wish to be understood as limiting myself to the precise details and arrangements of parts shown and described, but reserve the right to all modifications within the n scope of my invention.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination with a lock having slidable tumblers provided with recesses adapted to register, of a chain-bolt adapted to be inserted into said recesses and engaged and locked by said tumblers, and means for automatically removing said bolt from the lock when released by the tumblers, substantially as described.

2. The combination with a lock having slidable tumblers provided with recesses adapted to register, means for holding said tumblers normally projected forward, of a chain-bolt adapted, to be inserted into said recesses and having a groove adapted to be engaged by said tumblers to lock it and means for automatically removing said bolt from the lock when released by the tumblers, substantially as described.

3. The combination with a lock having slidable tumblers, said tumblers having recesses in their forward ends adapted to register and recesses in their rear ends, plates carried on the rear ends of said tumblers, a cross-bar rotatably located in said rear recesses adapted to engage said plates and slide said'tumblers in unison, of a chain-bolt adapted to be inserted into said forward recesses and having a groove adapted to be en gaged by said tumblers to lock it, substantially as described.

4. The combination with a lock having slidable tumblers, said tumblers having recesses in their forward ends adapted to register and recesses in their rear ends, plates carried on the rear ends of said tumblers, a cross-bar rotatably located in said rear recesses adapted to engage said plates and slide said tumblers in unison, of a chain-bolt adapted to be inserted into said forward recesses and having a groove adapted to be engaged by said tumblers to lock it, and means for automatically removing said boltwhen released by the tumblers, substantially as described.

5. The combination with a loclr having tumblers slidable concurrently or independently in the' same direction and provided with recesses adapted to register, resilient means for holding said tumblers normally projected forward, of a chain-bolt adapted to be inserted into said recesses and having a groove adapted to be engaged by said tumblers to lock it, substantiallv as described.

6. The combination with a lock having tumblers slidable concurrently or independ ently in the same direction and provided with recesses adapted to register, resilient means for holding said tumblers normally projected forward, of a chain-bolt adapted to be inserted into said recesses and having a groove adapted to be engaged by said tumblers to lock it and means for automatically removing said bolt when released by the tumblers, substantially as described.

7. In a lock, the combination with the locking mechanism thereof of a chain-bolt adapted to be engaged and locked thereby and means for automatically removing said bolt when released by said locking mechanism, substantially as described.

Signed at New York city, in the county of New York and State of New York, this 13th day of March, A. D. 1905.

RICHARD THOMAS ATKIN.

YVitnesses MORRIS F. BRAINARD, NE1L MAoNErLL. 

